Why Singapore lacked its planned radar specialists

Why were trained radar staff unavailable at Singapore for the proposed Force Z radar work?

Staff intended for Singapore are said to have been diverted to another threatened area, while the British expected Japan to wait until about June 1942.

Radar specialists intended for Singapore are said to have been redirected to another area thought vulnerable to a long-range attack. Singapore had lower priority because the British expected Japan to wait until about June 1942 before acting. The Japanese offensive is described as arriving roughly six or seven months earlier than that expectation. In this explanation, the shortage of trained staff reflects an assumption that there was still time to prepare Singapore.