Text users have been warned that operators plan on spending the morning flushing out unwanted texts from their networks, which have been clogging up the system.
The messages have become trapped after being sent to the wrong phone number over the past five years, since the last time such a tidy up was done.
Huge numbers have been sent to historical figures and characters from film and television who do not have phone numbers.
Although several patches have been put in place, network pipes are cluttered with lost text messages meaning that conversations can be slowed down on affected lines.
"We need to open up the pipes and re-route all the lost messages. Perhaps the operators can find a way to change all of the good wishes to wish everyone a happy Easter," said one source.
"I am not quite sure what we are going to do all the texts to Winston Churchill, though."
Workers have been equipped with mops and buckets of hot soapy water to scrub out pipes.
A spokesman from regulator ComOf IT defended the decision not to publicise the maintenance period.
"The operators insisted on the morning of 1 April, and we knew that nobody would believe us if we tried to tell everyone that text messaging might be slower all morning on that day," he said.
Yes, you've guessed it. This is our April Fool's story for 2004.
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Genuinely useful side-arm coming to PUBG in Update #23