no
cob will not run at 28.6 V
you need to pick a target current, look up the voltage from the datasheet (1212s are jsut over 36V at 1.4A)
then if you want to run 4 cobs you need 36X4
if you want to run 5 cobs you need 36X5
you have a little leeway but not much
for example 36X4 = 144V. if the driver give 143V that works. it may or may not dip the current output a bit.
but the absolute lowest you can run a 1212 is about 32V (and thats at a mere 0.1-0.2A).
under that they wont light up at all, and its questionable what the driver would do if youre trying to provide 1-1.4A at a voltage significantly under 36. (say 33-35.5V) they might flicker and never light up. better to have a little spare voltage than be right there
all that assumes series wiring with constant current drivers
you can read more here
