When the interest free period starts varies depending on the card issuer. Some companies give you 6 months from when you transfer your first balance, others from the "card open date" which tends to be at least a fortnight beforeyou actually receive the card itself!
Regarding on why it takes so long to issue a card.... whilst i can't speak for all credit card companies the one i work for is so slow for a number of reasons, these being:
1) The credit card computer system used is over 15 years old and was designed for american companies, the result is its slow and badly designed and this often leads to mistakes as data is misinterpretated by staff
2) The company is half way through closing its "all-in-one" credit card centre and laying off staff. These means there are less staff to deal with credit cards as the work is being distributed to existing *overworked* customer service and processing departments.
This is bad enough, but instead of one location we now operate out of eight different sites (Two of which are in India - including the important fraud and processing work - which isn't getting done properly....)
The end result of this is greater inefficiency and regular "blame games" - in which customers get passed from pillar to post as each department "doesn't deal with that"!!!
Oh, and with all these problems the company is focusing all its effort into attracting new customers...... so much so that we've been informed the budget has been cut on developing a replacement for our credit card system.... which means the inefficency and failures of the current set up will continue for the foreseeable future.
I'm not naming the culprit organisation but they are one of the biggest banks in the world........