A notice from Betfair so be aware you may not be able to access the api or you may get errors during this period:
We’re carrying out some maintenance tomorrow morning which will affect the API & Betfair website.
The work will take place between 06:30-07:15 GMT and for a short period during this time (probably no more than 5 minutes) the API & website will be unavailable.
Apologies in advance for any inconvenience this may cause. Of course we’ll do our best to keep any disruption to a minimum.