I'm in a similar position and those credits would be lifechanging.
The grants start out small (I think the first one was $3k) -- but then once you spend 75% of them you can apply for the next round, which for me they gave me $17k out of a possible $30k based on previous usage. After I spent around $15k for that over the next year I applied again and got $100k.
Just one note though that I already had an MVP that I was running on GCP at the time I applied (but I was within the $300 free credits that I started with so I didn't pay out of pocket).
Also good PR.
I like Firebase, but the moment the utility runs out we're heading back to AWS.
Just from a technical perspective I'd advise to avoid the firebase databases like the plague.
I've built a prototype on top of it and it's fairly rudimentary but you can make it work. My biggest concern is that there are no case studies I can find of people using it past the prototype stage and how the pricing/scalability works out at that point.
Love to hear from anyone who has gone beyond the prototype phase.
It's not completely wrong, but incomplete.
So if you want to work on building your business and not debug cloud provider issues, avoid the new upstart.