This justification is for a sole source 3-month extension of services / lease extension for two straddle carriers under contract SP451024P0028. The extension of services is required at DLA Disposition... This justification is for a sole source 3-month extension of services / lease extension for two straddle carriers under contract SP451024P0028. The extension of services is required at DLA Disposition Services Ft. Riley and Richmond to maintain operations.