Instead of waiting for a software update, get a one-button foot switch. Plug it into one of the expression inputs and assign it to whatever you like.
The software update will (most likely) never happen. Just sayin'.
you could always use a volume pedal and engage the tuner at heel
you could always use a volume pedal and engage the tuner at heel
This ! 
you could always use a volume pedal and engage the tuner at heel
Exactly what I do from day 1
Be aware, that enabling combo functions "pressing two switches at the same time" has an implication: The single switch functions assigned to those switches involved in the combo function cannot be processed before the button gets released. So associated sound changes won't happen when you hit those single switches, but when you release those. At the time you hit the first switch the software cannot know if a second switch will follow, since you will never hit those exactly at the same time.
you could always use a volume pedal and engage the tuner at heel
I've only one expression pedal that has no extra on/off switch and I use it for wah (bypass at heel.)
Be aware, that enabling combo functions "pressing two switches at the same time" has an implication: The single switch functions assigned to those switches involved in the combo function cannot be processed before the button gets released. So associated sound changes won't happen when you hit those single switches, but when you release those. At the time you hit the first switch the software cannot know if a second switch will follow, since you will never hit those exactly at the same time.
I understand Thank you!
I've only one expression pedal that has no extra on/off switch and I use it for wah (bypass at heel.)
The Mission Engineering EP1 is a good investment. The switch allows you to engage the wah, and when not in use is volume and you can set tuner at heel. Tuner button free for other purposes
I understand that your request is to make it optional but pressing 2 switches at the same time to switch to tuner is the opposite of what I would want.
In the heat of a manic stage performance wearing big boots, I often hit 2 switches by accident.....
When I used to use a FCB1010, it would result in confusion and the KPA going silent - one of the main reasons I upgraded as soon as the remote was released. Luckily this isn't the behavior of the remote. In other words, in that scenario I'd rather have the wrong sound than no sound so I don't want a backwards step. Plus the tuner button isn't easy to access although I never use it...I use my expression volume pedal..
