it really is unsafe to turn them forward facing before 1yo.
The UK is one of the only countries who allows babies to be turned before 1yo, longer is better. I managed to keep both of mine rear facing until 15mo.
You should easily be able to find seats that rear face up to 13kg. (which is the 0+ class, which allows RF up to 29lbs)
The issue is, that when they develop, the neck muscles are not strong enough to take the force of a collision when forward facing, and it can, at its most serious, cause internal decapitation.
Keeping them RF, means that during a crash, the force of motion is absorbed by the whole of the seat, rather than throwing the head/arms forward.
there is plenty of research out there, its not mumbo jumob. please, please, please, DO NOT forward face your child until they're at LEAST 1yo.