Shearer has been in temporary charge alongside fellow U20s coach Scott Kellacher for the last two matches following Terry Butcher's departure to Hibernian.
However he believes Saturday's 4-0 Scottish Cup victory over Morton will be his final game at the helm with the appointment of a new manager imminent.
Shearer said: "I think it's my last game in temporary charge. I'm sure they are well down the line in terms of getting a new man in next week.
"I've absolutely no idea who it will be. Fair play to the chairman because he's kept it very much to himself, so we all wait with bated breath.
"I wouldn't like it to go to another game put it that way, although I would have no problems if it does as we had someone watching St Mirren, so we're prepared.
"However, I would like the new man to get his feet under the table and see what a good bunch of lads that he's got."