Ideas for finding how to kill the Maintenance Sign.. its not in the root.

Before I jump in with both feet has anyone experienced this before.. the notorious Maintenance Menu that appears while wp is doing any updating.. and normally should go away when done.. A few times I have caught it not going away in the past however tis time there is no Maint file in the root to delete.. nothing there.. before I spend hours tracking this bugger down.. does anyone know where its coming from… the file is not there.. unless its hidden and I do have hidden files turned on ….I disabled htaccess so that the normal wp is not controlling it… but its still there.. i went into htaccess and put a code to force an htaccess abort and it did give the 500 error and removed the Maint menu..but with or without the htaccess it remaains…that is as long as the htaccess is not gening up a 500 error which it will if you put a bad code in it..
Thanks for saving me trouble shooting time if you have seen it..
view the maint sign here.. https://tampahomessold.com