So the option of extending the transition by two years will be eliminated in UK law.
Truthfully, this is mainly symbolism, in that a law can always be amended.
But it shows Johnson is intent on honouring the Tory manifesto commitment to terminate the transition in just over a year from now.
This will be seen as increasing the risk there will be in affect a no-deal trade relationship with the EU in 2021, with the UK having to incur painful EU tariff payments, because EU negotiators and leaders have warned there may not be time to negotiate a comprehensive free trade agreement by the end of next year.
But Johnson has repeatedly insisted he can pull off of a Canada-style free trade arrangement in that record breaking time.
The revised Withdrawal Agreement Bill is expected to have its second reading in the Commons on Friday.
Thanks to the 80-seat majority Johnson won in the election, the bill is expected to become law well before the 31 January deadline for the UK to leave the EU in a legal sense and enter the new transition arrangements.