An apparatus for thermal processing of nucleic acid in a thermal profile, the apparatus employing bath media and a reactor holder for holding reactor(s) each accommodating reaction material containing the nucleic acid and the reactor(s) being in any form such as tube(s) or wellplate(s) or chip(s) or cartridge(s), the apparatus comprising: a first bath; a second bath, the bath mediums are provided in the first bath and the second bath respectively, wherein the bath media in the first bath and the second bath respectively are maintainable at two different temperatures T HIGH and T LOW; and a transfer means configured to make the reactor(s) to be in the two baths (50, 51) in a plurality of thermal cycles to alternately attain: - a predetermined high target temperature T HT, and - a predetermined low target temperature T LT, while the apparatus is configured to adapt to a temperature-offset feature defined by at least one condition from the group consisting: a) the T HT is lower than the T HIGH, and b) the T LT is higher than the T LOW, the transfer means being operable by at least one mode from the group consisting: a temperature guided motion controlling means (TeGMCM) that is operable based on the real-time temperature as sensed by a reactor temperature sensor during thermal cycling, and a time guided motion controlling means (TiGMCM) that is operable based on the time-periods for which the reactor(s) are allowed to be in the baths (50,51), the bath medium in any of the baths (50, 51)being in any phase including air, liquid, solid, powder and a mixture of any of these; characterized in that the transfer means is configured to initiate lift-off of the reactor(s) from the bath(s) (50, 51) when the reactor(s) reach a first lift-off temperature that is lower than the T HT and a second lift-off temperature that is higher than the T LT to compensate for operational electro-mechanical delays that unwantedly cause over heating or over cooling of the reactor(s). a first bath; a second bath, the bath mediums are provided in the first bath and the second bath respectively, wherein the bath media in the first bath and the second bath respectively are maintainable at two different temperatures T HIGH and T LOW; and a transfer means configured to make the reactor(s) to be in the two baths (50, 51) in a plurality of thermal cycles to alternately attain: - a predetermined high target temperature T HT, and - a predetermined low target temperature T LT, - a predetermined high target temperature T HT, and - a predetermined low target temperature T LT, while the apparatus is configured to adapt to a temperature-offset feature defined by at least one condition from the group consisting: a) the T HT is lower than the T HIGH, and b) the T LT is higher than the T LOW, a) the T HT is lower than the T HIGH, and b) the T LT is higher than the T LOW, the transfer means being operable by at least one mode from the group consisting: a temperature guided motion controlling means (TeGMCM) that is operable based on the real-time temperature as sensed by a reactor temperature sensor during thermal cycling, and a time guided motion controlling means (TiGMCM) that is operable based on the time-periods for which the reactor(s) are allowed to be in the baths (50,51), the bath medium in any of the baths (50, 51)being in any phase including air, liquid, solid, powder and a mixture of any of these; characterized in that the transfer means is configured to initiate lift-off of the reactor(s) from the bath(s) (50, 51) when the reactor(s) reach a first lift-off temperature that is lower than the T HT and a second lift-off temperature that is higher than the T LT to compensate for operational electro-mechanical delays that unwantedly cause over heating or over cooling of the reactor(s). a temperature guided motion controlling means (TeGMCM) that is operable based on the real-time temperature as sensed by a reactor temperature sensor during thermal cycling, and a time guided motion controlling means (TiGMCM) that is operable based on the time-periods for which the reactor(s) are allowed to be in the baths (50,51), the bath medium in any of the baths (50, 51)being in any phase including air, liquid, solid, powder and a mixture of any of these; characterized in that the transfer means is configured to initiate lift-off of the reactor(s) from the bath(s) (50, 51) when the reactor(s) reach a first lift-off temperature that is lower than the T HT and a second lift-off temperature that is higher than the T LT to compensate for operational electro-mechanical delays that unwantedly cause over heating or over cooling of the reactor(s).