Citizenship ceremony question

[indian_in_uk]

Hi All,

I applied for naturalisation and got my approval on 9th August, dated 6th August.
I contacted the council today to book the ceremony and first date they have is 23rd August. I can not take the oath on 23rd as after the oath I would become british citizen and my ILR will become invalid.
I am travelling on 5th September and will be back on 15th September so I would like to have the ceremony arranged after 15th Sept (it is within 90 days in accordance with Home office requirements). The council would not give ma date after 23rd August as they have not sorted the date out yet , what I would like to do is to have a date after 16th september which the council would not provide at the moment.

so my questions is how important is to contact the council within 21 days to book the ceremony? Is this a problem if I contact them on 16th September to book the ceremony?

Thanks

[jms_uk]

Could you not call them from wherever you are traveling to after 23rd?