MORE than 100 Immigration Department posts are to be created to cope with the expected surge in applications following a move to allow Hongkong people to hold two passports simultaneously. The British Government this month yielded to pressure from Legislative Councillors and allowed Hongkong people to hold both British Dependent Territory Citizen (BDTC) and British National Overseas (BNO) passports until the 1997 handover. It had been intended that BDTC holders exchange their passports for a BNO document in phases over the next four years. Immigration officials expect the proposal to hold both passports - yet to be endorsed by Parliament - to more than double their workload. The 500,000 people who have given up their BDTCs for a BNO will be allowed to re-apply for a BDTC. The Immigration Department estimated that the demand for two passports will push daily applications to 2,300, more than double the amount the department handles at its eight branch offices. A source said existing staff would be unable to cope and the department had proposed to the Government the creation of more than 100 posts. It is understood the new posts will be filled by general grade staff or clerks since there are not enough immigration officers to take them up. The funding will come from the Government and does not need to go through the Legislative Council Finance Committee. The source said the public should apply for passports by post. The Government revealed yesterday that the phased programme for BNOs will begin on Thursday. The population will be divided into 10 groups which will be given deadlines to apply. Applicants who fail to observe the deadline will lose their right to hold both documents unless they are given dispensation by an appeal panel. The appeal panel will consist of two Legislative Councillors and a government official - the Secretary for Security, Alistair Asprey, or his representative. They will advise the Governor on all late applications for BNO documents that the Director of Immigration has refused to accept, but the Governor will have the final decision. All BNO passports obtained under the programme will be valid for 10 years from the issue date. But the Government has advised the public to use one passport in the remaining years before 1997 in order to reduce ''the risks of loss, theft and tampering''. ''To reduce the risks, the public will be advised to use only one of the two passports between now and 1997, preferably the BNO passport, which is the one with a longer validity period and will be used in the longer terms,'' the paper said. The detailed arrangements for the issue of BNOs and renewal of BDTCs will be explained to Legco members today and discussed by the Legco nationality sub-committee. The phased scheme, which would have required people to give up their BDTC passports, was endorsed by the Executive Council last December. However, Legco members opposed the proposal vehemently, claiming it contravened the Joint Declaration, which allows all BDTC passport holders to retain them until June 30, 1997. A delegation to London this month - led by councillor Emily Lau Wai-hing - persuaded the Government to reconsider the proposal and allow people to hold both passports.