See below, from the OED. The use we saw on the board is definitely adjectival. The OED describes this use as obsolete.
Everlasting, constant, perpetual. Frequently with agent nouns or nouns of action. Cf. Compounds 1c. Obsolete.
a1586 Sir P. Sidney Arcadia (1593) v. sig. Ss2v But the time of my euer farewell approcheth.1605 R. Verstegan Restit. Decayed Intelligence Ded. I take my leaue, desyring Almightie God..to bee your maiesties euer protector.1605 R. Verstegan Restit. Decayed Intelligence ii. 42 They haue bin the only and euer possessors of their countrey.1607 S. Rowlands Diogines Lanthorne 29 I know thy euer care For winters want..In Sommer doth prepare.1609 Epist. in W. Shakespeare Troilus & Cressida (2nd issue) sig. ΒΆ2 A neuer writer, to an euer reader.
