Millions of BBC One viewers have been told to check two channels ahead of the broadcaster's 'switch off'.

The major public broadcaster is in the process of converting its channels on satellite to HD.

As a result, the standard quality versions will be shut down as a part of the change.

The switch has already begun with BBC One rolling out the change of its regional and national versions of the channel.

Hereford Times: Freesat and Sky customers have been told to check two channels before BBC One moves to HD> ( Canva)Freesat and Sky customers have been told to check two channels before BBC One moves to HD> ( Canva) (Image: Canva)

BBC One South was scheduled to be first region to make the switch on January 23/24.

In the next few weeks, Freesat and Sky viewers with HD-enabled devices will be able to watch their local version of BBC One in HD on channel 101 (BBC One HD).

All regions should to be available by the end of February on satellite, and on (Freeview/YouView) by the end of April 2023, the BBC has said.

READ MORE: Original Mr Blobby costume sells on eBay for more than £60,000

READ MORE: EastEnders legend lands major Channel 5 role and returns to acting after seven years

 If you have an old Freesat set-top box, you may not be able to access BBC One when the SD channels close in early 2024.

This is because certain boxes are not equipped to handle HD.

After the switch off, you could be faced with a red screen which appears on the HD version of BBC One at 6 pm when the local news is on.

How will I know if my set-top box is affected by the BBC One HD change?

The BBC's change will only affect SD-only satellite boxes.

Freesat has launched a tool to check if you need to upgrade, you can find it on channel 799 on your device.

Meanwhile, Sky viewers with an old Sky set-top box could also be affected.

You can go to channel 105 to check if you also need the upgrade.

Your box will be capable of handling HD, if you can tune into Channel 5.

However, if you see no mention of HD, you will have an old SD-only box and you'll need to upgrade before the big BBC change.

For more information and guidance, visit the BBC website.