I know you posted this a while ago but thought I'd reply anyway. Last year it was first come first served with no sales criteria, minimum ticket points, minimum attendance, etc and it sold out in 8 or 9 minutes. Year before that they did do sales criteria, starting at 1000 points, then 500, 250, then any members.
If you're going about 10-15 times a season you should've accumulated quite a few points so if they do a sales criteria like they did for 21-22 then you've got a very good chance. If they do first come first served again then make sure to get onto the website an hour before they go on sale so you've got a good place in the queue.
Last year there were people who'd got onto the site 15-20 minutes before and had still missed out because they had a few thousand ahead of them in the queue.
Club hasn't announced anything yet regarding new sales but keep an eye on the season ticket page on the website and @ManCityHelp on Twitter as details should be announced within a week.
Regarding moving seats, I think you could put your season ticket on the exchange for a game and then purchase two tickets elsewhere. The refund you get for listing your seat on the exchange is only 1/19th of your ST's cost, which is likely to be a bit less than what you'll pay for another ticket though