Asset and liability recognition basic question

currently training so this may be a stupid question but I just want to understand. 

Is the asset and liability included in May accounts and tax allowances given. For example Year end is May. Company commits to buying an asset mid May. Company receives invoice dated May and cannot back out - deposit is paid in May. 

The asset is then being made and will be available in September (ie new vehicle reg). Asset is delivered in sept.

so just to check my understanding, as the invoice is raised and commitment is made and it is probable that the asset will come into the company. For the May accounts would the company recognise the asset, claim any allowable vat and recognise the liability or would it be recognised at the time of delivery in September?

i believe it to be May as that is when the commitment is made. The deposit would just reduce the liability in those accounts?

Thank you