I'd just like to generally reinforce the idea that you should find (and get!) your next job before you irrecoverably quit from your current one. It makes it much easier.
You may still have the same looks of betrayal from those who care that you've been there, and obviously you need to take into account any long-term projects[1] you need to hand over, when it comes to whatever notice you have to work (or, because of certain sensitivities[3] or owed vacations, leaving almost immediately), but that's going to have been the case anyway.
Having the knowledge that you are now not needing to look for a new job (however much free time you have gained, to do so) is probably as stress-reducing as getting the 'me time' (which it sounds like you get anyway, if you're on short-hours), especially in the
current employment climate. But if you can also work a (known-length) gap between the jobs, without stretching your finances to the limit in the process, you can probably get the benefits of both!
Just speaking from experience, here (not a personal vent, merely some hindsight I wish had been foresight, prior to that time). It was somewhat a different era, but I think things are going to be much the same in
this decade. And job-hunting might even be a bit cathartic (or, certainly more so than it would be under an aura of necessity!) and help you suffer the slings and arrows of outrageous managers, etc...
(The tricky bit is getting the references, I suppose. But it sounds like a problem, regardless, unless your current manager will say the nicest things about you in order to get rid of you... However, ignoring some of the reverse psychology aspects, perhaps approach the manager from the other store? You might even get an offer from him/her to switch site, if that's geographically amicable to you, or stir things up in your favour through the managerial rumour-mill if he's of the decent (and wise) sort who could do spark off such beneficial results.)
[1] I won't say that, as a shop assistant/whatever[2], you don't have any. I'm a total stranger to retail. And though I've technically been in a "service industry"-type position, I just couldn't stand having to deal with... <shudder>... having to talk to strangers... <double-shudder>.
[2] Sorry, probably just insulted you or something, without meaning to, by using a wrong title. As long as you're not wedded to the title "Customer Service Enhancement And Fulfilment Co-Manager Executive (junior grade)", or somesuch.
[3] Working in a drugstore, the policy might be to keep you away from stock, to avoid sticky-fingers? When I was leaving a data-heavy industry position I was similarly disconnected from all 'tempting' data as part of the leaving process... But then
I'd previously written the policy on what to do, in those circumstances, so I knew it was going to happen!