To resign from Second job after just a few Weeks?

[Onemorebox]

My PT Job became stale, no growth prospects and most days became a boring routine with no challenges whatsoever. I found a second job which looked a lot more hopeful in terms of progression and varied responsibilities. They're both part time and I've been transparent about working for both.
Since I've started my second role my first role has upped it's game and thrown everything at Me, more Money, training, I've been assigned projects, brought into senior meetings... basically everything I asked for every time I had a review / appraisal.
Now to the point, WIBU to resign from my second role whilst still under probation? They're good people and are really pleased with Me but I don't feel like I need to pursue development with them anymore? WWYD?
Hopefully that all makes sense!

Quit.

If you’re certain you want to leave just be honest and give them plenty of notice so they’re not left short-staffed. These things happen all the time and are a bit of an annoyance but not the end of the world.

The first job are only doing this now to stop you jumping ship to number two, I'd be suspicious that it was going to carry on if you've told them previously what you needed and they ignored you, it could be a turning point but only time will tell.

I'd be wary of jacking the second job just yet, have your bosses spoke to you about why they are able to offer you more now? Do you not want to do both?

@sandyhappypeople Take on board everything you've said, it is suspicious but I think they've had a bit of a 'scare' as such with Me taking on another Position elsewhere for a much larger Company (same business).
Also since I've started the second job there's been lots of movement in my first job with Staff, completely coincidental but prospects of progression are on the horizon and from what my Boss has said, I was always first in line. I'm trying to do both at present but there's only so much 'Oomph' I can give to one job - I assumed i would fall head over heels for the new company and quit my old job straight away.
When in fact by old job seems to outweigh the benefits of the new one currently!

I think that answers your question then! 😂

No you wouldn't be unreasonable to leave the second job at all, probably better now so that they can find someone before you are fully integrated there, and you can always offer to work a longer notice period if you feel a little bad about it.