WWI did not officially end on 11th November 1918. The treaty negotiations at Versailles continued long into the following year.
In Britain the Peace Committee met for the first time on 9th May 1919, they outlined a celebration running over four days, including a Victory March through London, a day of Thanksgiving services, a river pageant, and a day of popular festivities.
The morning of Saturday July 19t...h 1919, saw thousands of people gathered across London, they had flowed in overnight by train and bus. Numerous representatives of the allied nations were in attendance. The Peace March was one of the most impressive spectacles ever witnessed by Londoners and the world. Nearly 15,000 troops took part in the march, led by the victorious Allied commanders
On the morning of the 19th July King George V issued a message to the wounded soldiers.
"To these, the sick and wounded who cannot take part in the festival of victory, I send out greetings and bid them good cheer, assuring them that the wounds and scars so honourable in themselves, inspire in the hearts of their fellow countrymen the warmest feelings of gratitude and respect."King George V.

(picture from https://www.forces-war-records.co.uk/Library/Search)