IMR4895 vs H4895 and IMR 4350 vs H4350 for 6MM AR and 6MM CM

[RMB]

I am at a point that I to purchase more powder. I am reloading for 6MM AR (H4895) and 6MM Creedmoor (H4350). I cannot find the H4895 or the H4350 in stock and can only find the IMR powders.
So I plan on not quite starting from scratch....but working up loads for both...

For the 6MM AR (Semi Auto) my load was:
Hornady brass
205M Primers
87 grain Vmax
28.6 Grains H4895
COAL 2.188"
I plan on starting at 27.0 grains and "working back up" to 28.6.....
Is this an acceptable plan...Will I see more pressure with the IMR 4895?

For the 6mm CM the plan is the same.....but in a bolt action.
Hornady brass
210M Primers
95 grain SMK
44.1 Grains H4350
I plan on starting at 42.0 grains and working back up to 44.1...
Same question will I see more pressure with the IMR 4350?

Thanks in advance!!

 

[MarinePMI]

4895 is pretty close between IMR and Hodgdon. 4350 has not been IME.

 

[GMZ]

Midsouth shows 8# of H4350 in stock

https://www.midsouthshooterssupply.com/item/0003443508/hodgdon-h4350-smokeless-powder-8-lbs