Johnson suffered a knee injury in the 1-0 defeat to West Bromwich Albion on December 2 and has missed nine games.
His creativity and goals from an attacking midfield role have been missed but he could possibly return to the squad for Saturday's clash with Charlton Athletic at Deepdale.
Bayliss rolled his ankle in a bounce game against Accrington Stanley on Tuesday, one in which Scott Sinclair scored, and will be out for a a few weeks.
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Speaking at his pre-match conference at Springfields on Thursday morning, Neil said: "DJ has been training with us for the last couple of days, while Andrew Hughes will be touch and go for this game.
"Our only disappointment is Tom Bayliss picked-up an injury this week.
"Tom has been doing a lot better of late and we were looking to try and involve him more.
"It is more than a niggle, it happened in the bounce game the other day, he rolled his ankle which is not great."
Neil wouldn't say if he was tempted to fling Johnson straight back in, bearing in mind the seven-week absence.
"Maybe we have to think further ahead with DJ, we will have a look at him over the next day or so," said Neil.
"He is still our top goalscorer which shows how much we have missed him.
"By now he has missed about a third of the games we have played.
"Whenever you have key players out you are always going to miss them"
Bayliss' injury will keep him out for a time, with Billy Bodin also out after being injured by a tackle in training last week.
With regards the length of Bayliss' absence, Neil said: "It is difficult to say exactly at the moment, he has definitely rolled his ankle so it is more a case of weeks rather than days.
"Billy Bodin will be the same."