Does daily brushing stop progression of gingivitis/periodontal disease until my cats consult and cleaning?

I have two cats one has gingivitis bc it’s only red while the other seems more serious. I noticed it recently and my primary vet charges $900 for a simple cleaning so I found a nonprofit clinic that does cleanings for $315 and grade 3-4 cleanings with extractions for $600 which I can afford but they’re booked out 3 months. I scheduled a consult which they require before procedures for June 16th. If I brush their teeth daily until then will it be okay for them to not worsen until their appointments?

My cats are:

Choco - 5 y old Scottish straight neutered 15 pounds I think he has the more progressive disease

Ori - 5y 10 month Scottish fold spayed 9 pounds she seems to have inflamed red gums and yellow teeth but no blackness