Fast Probe 427 fw help please

[okcub2010]

I'm trying the Smith3D 427 fast BL Touch 5x5 fw on a newly upgraded E3 pro with a new V2 display and a older V3.0 BL Touch. All is working except the bl Touch probe retracts for each fast probe? Using the same but 422 fw on my V2 printer with a newer bl touch v3.0, the probe stays extended for 2 taps then retract until it moves to the next position? Is this because of the bl touch being a newer V3.0 instead of a older V3.0 I'm trying to use on the 427 install? I'm OK with buying a V3.1 blt is its required but have to ask first to verify it's necessary. I could swap the blt V 3.0 to the 427 board to test it but trying to avoid that.
Thank you for any help on sorting this out.

Update FYI
It seems the early bought v3.0 doesn't do fast HS probing but the later just befor the v3.1 was released does! So it is probable a blt fw issue with the early v3.0 that's preventing the HS speed option.
I'm ordering a new 3.1 blt to confirm this and the older 3.0 will be a spare or gift to locals still using 8 bit boards.
at this point no reply is necessary to my original question but I do hope it will help others upgrading a older ender with a bl touch