“The question as to whether the selection grade is a condition of service or not, depends upon either the service rules governing the service conditions and/or the terms and conditions of employment on a particular post which are laid down by the competent authority and accepted by the employee. There is nothing on record to suggest that selection grade was ever prescribed as a condition of service for Sectional Officers/Junior Engineers. On the other hand, the petitioners themselves have admitted that selection grade was granted to them to compensate due to stagnation in their career as every one of them could not expect further promotion to the post of Sub Divisional Engineer. Thus, it is the pleaded case of the petitioners themselves that selection grade came to be granted to them as a substitute for promotion. It is well settled that promotion is not a condition of service and cannot be claimed as a matter of right except that if promotional avenue is provided, the concerned employee has a right ot be considered for promotion subject to his eligibility and suitably. In view of this, it is difficult to accept that by laying down certain eligibility conditions for the grant of selection grade, service conditions of the petitioners have been adversely altered.”