If ladybirds like their hibernation site they (or their offspring) tend to go back to the same place year after year, which is fascinating! So the same might happen next year. I once worked in an office in a very old house and every winter, if you opened the windows (often to let hibernating queen wasps out too),I was showered with hibernating ladybirds. Many were sosqueezed into the frames it was difficult to close the window without squashing them. Try making a ladybird hotel up in the window, away from sunlight. Upside down paper cup stuffed with shreddings (a bit like a dahlia earwig trap outside) often works, but they may not move in now, might work next autumn. Are they harlequins or "ordinary". Might be worth checking the ladybird website!