In fact the timing “fits”...
Eurotwit, I am starting to go back to my original thought of two or three perps. One perp does not fit ... based upon the number of devices found and the ability to move the necessary ammunition and firepower to carry out the attack on the island. It would seem someone would have been more alert after the initial bomb going off ... I could be wrong yet the pieces, for me, do not fit.
Breivik apparently diabolically used the initial bomb to help the island massacre; he showed up and said he was there BECAUSE of the threat from the earlier bombing to provide security, and asked the kids to gather around...then he started shooting.
One video news clip I saw showed a van he'd brought onto the island. The ferry operators are said to have bought his story that he'd come to check on the island because of the blast in Oslo.