67 DIGs posts are vacant in CAPFs

A large number of posts of DIGs across CAPFs are vacant for the last several years. Presently 67 posts of DIGs are lying vacant. Maximum 21 posts are vacant in SSB followed by CRPF where 16 posts of DIGs are vacant. 13 posts in CISF, 11 in ITBP and 6 in BSF are vacant. Sources said that despite 67 clear cut vacancies, CAPF officers with 27 - 30 years service are waiting for promotion as DIG. Are these posts across CAPF kept vacant since several years deliberately for somebody to come on deputation?.