Mayhaw jelly is available commercially. It's from Florida, which claims a "centuries old tradition." I've heard of mayhaw, have never had it, but then I've never been outside of Orlando. I have had crabapple jelly (have made crabapple jelly) and I would characterize it, as with most "delicacies", as "thing we don't really want to eat but at one point we were poor and we ate it and now we make auslanders eat it as a ritual to welcome them to our tribe." The proper spelling of "y'all" is "y'all" because it is a contraction of "you all." Your boss is wrong, as the deep south usually is. West Texas used to use "y'all" to address a group of people but since Texas now aligns itself more with the South than the West, Southern appropriation has dominated for at least 30 years. Plural "y'all" dominated as far west as Amarillo in the '90s but east of there, singular "y'all" was king. My personal theory is southerners use "y'all" singularly and "all y'all" plurally much the same way German uses "sie" formally. It is the hillbilly version of the "royal we".