SANTA CLARA, Calif. -- After another whirlwind offseason filled with the usual staples like quarterback quandaries and injury updates, the San Francisco 49ers will finally get back on the field Monday for the closest thing the NFL offers to an actual practice in May.

And while the answers to many of their remaining questions won't come for months, the Niners can begin collecting more information before training camp kicks off in late July.

With that in mind, here's a look at some of the most pressing issues facing the 49ers as they open organized team activities.

Who's under center?

No reputable list of 49ers issues can start without discussing the quarterback. They believe they have their quarterback of the short and long term in Brock Purdy, but they will not have him for OTAs as he continues to recover from surgery on the ulnar collateral ligament in his right (throwing) elbow. Purdy appears to be on track and is expected to begin a throwing program in early June, which will give the Niners a better idea of a return timeline.

Meanwhile, the Niners have three signal-callers -- Trey Lance, Sam Darnold and Brandon Allen -- under contract. Coach Kyle Shanahan has said Lance and Darnold will get reps with the first team in the offseason program. That's not necessarily indicative of a pecking order, but the 49ers would like to generate as much competition as possible between that duo rather than just reinstalling Lance as the starter while Purdy recovers.

"We'll get to training camp," Shanahan said. "Hopefully we'll get Brock back soon ... You never know how much we end up doing in the OTAs sessions, but it has been good having two guys out there throwing."

This is a particularly important offseason for Lance, who has been fully cleared from the broken right ankle he suffered in Week 2 last season and is further removed from the chipped bone in his right pointer finger that slowed his development as a rookie. Despite persistent trade speculation, general manager John Lynch has said he believes Lance will be a 49er in 2023. If that's the case, it's up to Lance to determine what his role will look like as Darnold acclimates to a new offense.

"Trey knows exactly where the situation is," Lynch said. "His mindset is all about competing and I think that's exactly where his mindset should be. We're excited about the position he's put himself in with the work he's done this offseason to, No. 1, get healthy, No. 2, improve upon some things that he really wanted to improve upon ... We're excited about Trey's ability to go compete for a job."

When will Nick Bosa get his big payday?

As is custom, Bosa has spent his offseason in Florida training with brother Joey. That's no cause for alarm, as this has been Bosa's M.O. for years. Bosa is, however, next in line for what figures to be a market-setting contract extension for a defender.

The Niners and Bosa have said all along that they will be patient when it comes to getting a deal done. Recent precedent would indicate that there's not much to worry about. In recent years, the Niners have gone through their offseason business before turning their attention to big-money extensions. And all of those -- tight end George Kittle, linebacker Fred Warner and receiver Deebo Samuel -- were completed either right before training camp or soon after it opened.

It's safe to expect a deal for Bosa to come in the same window as the others, if not a bit sooner.

"I've stated many times that's a priority for this offseason," Lynch said. "History says that we have a really good track record of doing that and making that come to fruition. I'm excited about working on that when the time comes."

Are more roster moves coming?

Earlier this offseason, the 49ers executed simple contract restructures on cornerback Charvarius Ward and Warner to create needed salary cap space entering free agency. Then, just before the NFL draft, they did another with running back Christian McCaffrey, opening up $8.576 million in additional space. That move prompted some to wonder if they were preparing to make a move for another veteran at a position of need.

According to Lynch, the primary reason for the move was to create space to sign the team's rookie class, but he also kept open the possibility of looking around.

"It just gives us some room," Lynch said. "We'll see. We're never going to stop looking for players that can help, and it's just a lot of the slots are filled, and where they aren't, we'll go add to it if we need to."

The Niners have a full 90-man roster entering OTAs but will likely create even more space when they extend Bosa, which means they have some flexibility if they want to pursue veteran help on the offensive line, at edge rusher or elsewhere. Even if nothing is imminent, OTAs offer a chance for Shanahan and Lynch to assess what they have and move accordingly if they feel more is needed.

How will the offensive line look?

The 49ers return four of their five starting offensive linemen from last season but must replace stalwart right tackle Mike McGlinchey, who signed a five-year, $87.5 million deal with the Denver Broncos in March. After declining to invest free agent money or significant draft resources into the position, they made it clear they believe McGlinchey's replacement is already on the roster in the form of swing tackle Colton McKivitz.

McKivitz has started just five games since the Niners drafted him in the fifth round in 2020, but they believed in him enough to sign him to a two-year, $4.56 million extension this offseason.

"You can win with Colton," Shanahan said. "He’s been here for a while. When he has played, we have won games with him ... I get how not everyone else knows about them as much, because they haven't seen them, but I mean we were going to that draft hoping to find depth and hoping to find some competition, but to go into that draft and think you're going to find someone to start over someone like Colton, or as good as Colton can be and has been, would be very unusual."

The Niners' hope is that McKivitz can follow the path of center Jake Brendel, a relative unknown who took over the starting center job in 2022 despite much outside consternation and played well enough to earn a four-year, $16.5 million deal in March.