Upgrading 2 day Ticket to Annual Pass

[APotterMom]

We are going to USH for 2 days right after Christmas buying a 2 day ticket. Can we upgrade to a Silver or Gold annual pass on our second day by paying the difference in price? The days would be blackout days with the annual passes so we can't buy the passes first. Has anyone done this?
Thanks in advance.

 

[com1padres]

I bought a two day ticket in August and used my second day yesterday. As we left last night, I upgraded to silver annual pass. Regular price is $109 for the upgrade, but I was eligible for a $69 promo. My annual pass will expire the same day of my first admission. YMMV, but that was my experience. Good luck!