Byrne added the club will have several irons in the fire if Martin O'Neil's first-choice options do not come off.
While the ideal scenario will be to get all the players in before pre-season, she concedes in reality this will be unlikely to happen.
Byrne told the Shields Gazette: "People sometimes say that the search for new signings begins on February 1, but I think it actually begins earlier than that, it begins in January.
"It begins then because you're looking at possible signings that can't happen in that window, but might happen in the next.
"The ideal scenario is to get all the players in before pre-season - that's something you always hope for - but you aim for it in the full knowledge that in reality it is always unlikely to happen."
She added: "You always have to have a Plan B and C as well as a Plan A.
"Nine times out of 10, you get your Plan A - Steven Fletcher is one example, Martin O'Neill always wanted him and was prepared to wait - but you always have to other options in the background. It provides a safety net.
"The way it can work at times, it's no exaggeration to say you might be looking at 15 players for just two positions.
"It can be as complex as that, which obviously makes the windows very high-pressurised affairs."