No, because things that are obviously contra to the currently accepted chronology of the Bulgarian war (see e.g. Holmes 2005) are included in that map. Apparently Lessman read a book that mistook the Spercheios campaign for conquest instead of an extended raid; he has Bulgaria extending further south than is reasonable, and fails to include the Byzantine reconquest of Triaditza/Serdike/Sofia as well.Wouldn't that be true for almost all maps depicting a time before modern border demarcation?
Perhaps more relevantly for you, he also doesn't really do anything with the then-ongoing Buyid/Buwayhid civil war (despite it being fought on relatively similar terms as the Bulgarian war with the Byzantines), confusingly depicts the 'Abbasid caliphate as "independent" despite the Buyids/Buwayhids having exercised military suzerainty over that area some years before, and seems to messed up the Caucasus in general.