CGT Land Registry Transfer Delay

In April I applied to transfer a half share of an ex-rental property into my wife's name. We have since decided to sell and have accepted an offer. HMLR have acknowledged the application but it's not yet been completed. CGT would be significant if the sale proceeds in my name only. Q1. If I go ahead with the sale and contracts are exchanged between TR1 application and completion, am I solely responsible for CGT or would HMRC accept retrospective joint ownership? Q2. If I ask solicitors to expedite the transfer, how quick could this be? Q3. Should I cancel the sale and lose the buyer until HMLR have completed the transfer deeds? Q4. This situation isn't uncommon, how likely is it to put off buyer's solicitor? Very grateful for your thoughts.

Hi Howard Agutter,

Q 1. If I go ahead with the sale and contracts are exchanged between TR1 application and completion, am I solely responsible for CGT or would HMRC accept retrospective joint ownership? 
A 1. As you would also need to notify HMRC of the transfer, it won't be done retrsopectively and if the property is in your sole name, you would be liable for all the capital gain. 
Q 2. If I ask solicitors to expedite the transfer, how quick could this be?   
A 2. We cannot comment on that as you would need to contact HMLR  
Q 3. Should I cancel the sale and lose the buyer until HMLR have completed the transfer deeds? 
A 3. That is a decision for you to make.
Q 4. This situation isn't uncommon, how likely is it to put off buyer's solicitor?
A 4. We cannot comment on that as its not a tax question as such.

Thank you.