The Germans were seriously considering an airborne attack on the island of Crete. They had considered a purely seaborne attack on the island, but didn't think that the Italian navy was reliable enough for that to be an option. They had seen success with airborne troops in Holland and Corinth, so they were planning on an airborne attack. They had a relatively large airborne force, including Para troops and glider-borne soldiers.
The British were aware that they could face an airborne attack on Crete. Staffs in both London and Cairo were planning for a defence of Crete from an airborne attack. The overall situation was so desperate that defending against an airborne attack on Crete did not get the attention that was needed.
There was a lot of action in Aril 1941. General Cunningham, the admiral's brother conducted a brilliant campaign in East Africa defeating the Italians and their colonial allies. The 2nd Armored Division was defeated and the 9th Australian division was pushed back, eventually being isolated in Tobruk. The Germans captured three British generals, including Richard O'Connor, who had defeated the Italians and who had captured Cyrenaica. AS early as 11 April, the 9th Australian Division, one 7th Australian Division brigade, and the 3rd Armoured Brigade were defending the former Italian fortress at Tobruk.
This is based on the account in "Greece, Crete, and Syria" by Gavin Long.