Temp loss of freeview channels

[Quick silver]

For the past three evenings (late on) I have been losing a lot of the commercial TV channels & the box message is: 'Check your aerial connection'

The next morning everything is back to normal.......it's a pain in the aris when it goes off halfway through a film!

I've been told that the digital switchover is happening now in the Northwest area that i receive signals from - could that be effecting my viewing or does the box need to go back?