All that can presently (September 2019) be gleaned about P.L. Eubank from sheet music covers and by internet searching is that he has 2 works published between 1912 and 1914.
Of ragtime interest is
Mutt and Jeff Rag (1912) published by
P.L. Eubank Music Publisher, San Antonio, Texas, USA.
Surfers are welcome to contribute information about this composer.