Aldridge may have been negotiating for a contract at one of London's patent theaters not long after he left the Royal Coburg in November 1825. The advertisement for his appearances in Exeter in April 1826 spoke of him performing there “Previous to his Engagement at the Theatre Royal, Drury Lane.” The same was said on the playbill heralding his enactment of Othello in Penzance in August that year. When he took the stage in Halifax in January 1827, the playbill stated that he was “engaged to appear at the Theatre Royal Covent Garden in the course of the present Season.” Such an engagement “during this season,” “for the ensuing season,” or “in the course of the present season” was also trumpeted in publicity materials for his appearances in Newcastle upon Tyne in March, Lancaster in September, and Nottingham in November. The playbill for his second night at Newark on November 26 claimed that he “makes his Appearance at the Theatre Royal, Covent Garden, at the End of the Month,” but two nights later this was amended to read that he “will perform the same Characters [Gambia and Mungo] this Evening, as he will make his Appearance in, at the Theatre Royal, Covent Garden, at the end of next Month.”

The promised engagement never took place that year, but it continued to be promised on playbills in 1828 and 1829 as Aldridge made his rounds of Coventry, Worcester, Lichfield, Ledbury, King's Lynn, Belfast, Glasgow, and Londonderry. By the middle of November 1829, rumors were starting to swirl in the London theater press, too. Both the Theatrical Observer; and Daily Bills of the Play and the Monthly Theatrical Review reported that “it is said that an American Keane [sic], alias the Black Roscius, has signed an engagement with the Covent Garden Managers; but that previous to his playing there, he will act for one night at the Haymarket Theatre, which will be opened for a benefit.”

There must have been grounds for such claims and rumors. It seems unlikely that such statements would have been made year after year if Aldridge did not have reason to believe that he stood a good chance of securing an engagement at Drury Lane in 1826 and at Covent Garden sometime between 1827 and 1829.