Has the updated vaccine even been received by pharmacies? I thought it was September, maybe end of August (so now). Either way, what they are SUPPOSED to do, when a new/updated formula comes out, is to get rid of the old formula, so they only distribute the new. Key words... "supposed to".
I'm guessing that you'd be able to get a definitive answer once they've received the new formula as they are supposed to know what they'd done with the old (get rid of it (send it back?)). The latter is JMO from info given to me by my local pharmacy when I asked what they did to the old stock the first time there was a formula change. I did not want to be given the old formula, which happened to 20 people here at a vaccination event. The 1st 20 in line got the old vaccine. I posted about that back when it happened (~1 yr ago). They were contacted about the error but most choose not to believe it and were talking to neighbors on Nextdoor (an app to talk to neighbors). Someone contacted our Healthy Authority to inquire about it and shut down the rumors and it was true. They posted the communication they received from the HA.
So... best to make sure as you're doing. If it was me I wouldn't go until I was assured that they indeed sent back the old stock when the new was received. The bottles are also relabeled with different colors so the pharmacy doesn't make that mistake. Also info from an old post of mine long ago. I had contacted the CDC for that answer and posted their response to me here, way upthread.