I now believe I can redeem the points now, but need not travel until the end of June, or even beyond?
I converted 1400 points into 4 First Class Single tickets yesterday, so I hope I can help.
On eastcoast.co.uk, go to Sign In > My Account > My Rewards. This shows you the number of points you have available and the number of tickets you have available to book.
Yesterday, I had 1406 points and 3 First Class Single tickets remaining available from a conversion I made in September.
On converting 1400 points into 4 First Class Single tickets, today it shows I have 33 points and 7 First Class Single tickets available. I expected my balance to be only 6 points, but I think that overnight 27 pending points must have matured.
I find it helpful to adjust the "Recent activity" list to show "all time". I have found that conversions do not always appear immediately in the "Recent activity" list. Don't worry about that. In my experience, they're always there 24 hours later.
Two entries are relevant in my "Recent activity" list. For 30 September 2014, an entry states "
1400 Points used for Rewards Leisure First Class Single Tickets - Expires on 30/03/2015". For 31 December 2014, an entry states "
1400 Points used for Rewards Leisure First Class Single Tickets - Expires on 30/06/2015".
This means that I have until 30 March to book tickets with the remaining 3 of the 4 I converted last September and I have until 30 June to book tickets with the 4 I converted yesterday (but appear on the account dated today).
But I don't need to travel by these dates. If I book the last 4 tickets in late June, I can travel on any date where Rewards tickets are not barred within the then booking horizon. That probably takes me to the 3rd week in September 2015.