Both midfielders had made significant progress in their respective recoveries from injury having been expected to miss much of the remainder of the season.
However Saturday's game with Plymouth Argyle is likely to come too soon, with neither man having yet returned to full training.
"Herbie has been back on the grass and hopefully he'll be training with us on Thursday," McCann said.
"Ben will hopefully be back with us this week, but if not it'll be the game after.
"Hopefully he'll be back on the grass with us this week as well.
"Herbie is probably a little bit ahead of Ben in terms of his recovery at the minute.
"Ben is still feeling it at the minute.
"Whether we take a risk on either one of them at the weekend, we'll see.
"It doesn't give them much time for the game with them not coming back until Thursday and Friday."
There has been further positive news on Joe Wright and his prospects of returning before the end of the campaign.
The defender was back training on the grass this week for the first time as he continues his recovery from an ankle injury.
McCann said: "It's the first time he was on full body weight running on Monday.
"He'd done the AlterG running machine at 75 per cent body weight but now he's back up to full and he's feel really good.
"He's coming along really well.
"He'll get through this week with the physio, then he'll be handed over to the sports science team for a bit of conditioning for a couple of weeks.
"Then he'll be back with us."