no, it was only extendable by the unable to travel due to covid extension. If that's not extended then you'd need to leave the country or convert to a different visa.
most people didn't think they would've extended it last month but they did. If you want me to guess, and that's all it is, then no I don't think it will be extended again but we're unlikely to know until a few days before or even on the day itself.
Just shows why you should book direct with an airline and not with a 3rd party. A quick look on Scoot's website shows they don't fly that route on Thursdays.
Nothing required to leave Thailand. If anything is required it will be as determined by the airline and the country you're flying to and transiting in, if applicable.