3 mobile - mystery free 500mb?

Hi,

I have a 3 dongle for backup internet, only ever have topped it up twice in the past six months and owned it for this length of time.

I connected it again for the first time in months, just to see what the signal strength was and my account was credited with a free 500mb internet allowance.

Any ideas why? Is this a teaser to get me back on? Still very grateful because it is twice as fast as my landline connection!

You should have had an email about it.

Free 500MB and 3 months to use it in.

Ah that would make a lot of sense.

I don't have an email address registered with them - I just use a PAYG dongle, so they have very little on me.

Thanks, thought it must be some promotion or other.