EC Received, Question regarding dependents travel

[marupa]

I have received by EC from 3/1/2008 to 3/1/2010

While applying for the Visa, I applied for me, my husband and my son.
I have and arranged work and have to report to work on 21st Jan, so I have to travel by 19th Jan

But it would be difficult for my husband and my son to join me so soon as there is winding up to be done at home. Also it is extremely cold out there and I don’t want my son to land there in the peak of winter.

My question is since in the VAF2 I have mentioned that my spouse and child will be travelling with me, should they necessarily travel with me or can they travel on a later date?

Also in the VAF2 Guidance notes with regard to my son’s application says

“4.27 If accompanied, please provide full details of up to two
adults who will accompany you
Please provide details of accompanying adult’s full name, date of
birth, passport number, address and telephone number. Up to two
adults may be listed as accompanying you (the child).
These details will be recorded on your (the child’s) visa. If in the
future you (the child) want to travel without the named adults, or
with different adults you (the child) will need a new visa.â€