"Sorry, this service is unavailable
You will be able to use the service from 11:30pm on Saturday 11 May 2019."
Apparently for a few hours/days only.
Can't be right:-https://www.gov.uk/government/publications/annual-tax-on-enveloped-dwell... says:
HMRC wrote: Service availability
Full service available.
Ive got clients who have been getting a 'please try again later' message for the last two years - and therefore have to keep filing by paper,
HMRC are aware, and don't give a [***]